Hello @Paul Jinwoo Lee ,
welcome to this moderated community forum.
While you check the Stream Analytics connection as @-- describes, can you confirm the Stream Analytics job has its own consumer group?
Consumer groups are set on the built-in endpoint in the IoT Hub:
Each consumer group gets its own copy of incoming messages. If not set, consumers have to use the same group and thus the same stream resulting in errors.
Next to that, do you use routing together with the built-in endpoint?
If that is the case, you need to create an extra route for the built-in endpoint.
See the text on the Rotes page:
If so, your normal route is picking all messages up, leaving no message for (the now) fallback route.
Just add that extra route of listening to 'events'.
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